Blog Roll

Domagal-Goldman and other researchers spend a lot of time thinking about the best biosignatures, or signs of life, to look for in the atmospheres of faraway planets.

Two good candidates are oxygen and methane, both of which disappear from atmospheres without replenishment. While each substance can be created by geological as well as biological processes, detecting both oxygen and methane in an exoplanet's skies simultaneously would be strongly suggestive of alien life, many scientists say.